Visualizing actor programs using predicate transition nets

The Actor model of concurrent computation uni es the functional and object-oriented programming language paradigms. The model provides a exible basis for concurrent programming. It supports local state, dynamic creation and con guration, and inherent parallelism. Because of the uidity of Actors, specifying and debugging actor systems is often considered di cult. We believe visual programming techniques are of fundamental importance in addressing powerful concurrent systems of this nature. Not surprisingly, a number of methods to visualize actor programs have been proposed. We give an outline of visualization techniques and their relation to actors. We then discuss one such proposal, namely the use of Predicate Transition nets, to visualize actor programs.